1. Federal Department of Home Affairs FDHA Federal Office of Meteorology and Climatology MeteoSwiss Overview of Swiss activities R. Stübi, D. Ruffieux, B. Calpini Federal Office of Meteorology and Climatology, MeteoSwiss, Switzerland Acknowledgements for the different “teams” behind these activities: Payerne team Arosa team Collaborating laboratories

2. 2 Swiss organisation n Main task of MeteoSwiss is monitoring n Applied research in support to monitoring n R&D are mainly devoted to Universities and Research Laboratories Outline of the presentation n Examples of ozone time series measured in Switzerland : Arosa, Payerne, and Nairobi n Data quality control: Brewer triade stability n Applied research : Automated Dobson

3. 3 Outline of the presentation n Examples of ozone time series measured in Switzerland : Arosa, Payerne, and Nairobi n Data quality control: Brewer triade stability n Applied research : Automated Dobson

4. 4 Arosa station total ozone monitoring site n Arosa Alpine site (1850 masl) with Brewer and Dobson n Monitoring activity focused on total ozone and Umkehr n Triade of Brewer : Brewer : B040 (1988), B072 (1993), B156 (1998) n Triade of Dobson : D101 (1968), D051 (1991), D062 (1993)

5. 5 Arosa long term total ozone series Yearly mean of Dobson total ozone column [DU]

6. 6 Payerne station ozone monitoring site n Payerne Mittelland site (491 masl) with radiosounding and microwave radiometer (in collaboration with Uni Bern IAP) n Monitoring activity focused on profiles

7. 7 Payerne 2002: change from BM to ECC ozone sondes After a larger series of BM - ECC dual flights, Payerne changed to ECC sonde No difference are noticeable at the different levels !

8. 8 Microwave radiometer GROMOS time series (Uni Bern IAP) Microwave radiometer SOMORA time series (Payerne)

9. 9 Payerne is supporting the Nairobi ozone station n Radiosoundings since 1996 n Dobson measurements for 1984 – 1999 and again since 2005 (MCH resp.) n Surface ozone since 2012

10. 10 Outline of the presentation n Examples of ozone time series measured in Switzerland : Arosa, Payerne, and Nairobi n Data quality control: Brewer triade stability n Applied research : Automated Dobson

11. 11 Times series of Brewer B040 total ozone Single Brewer values total ozone column [DU]

12. 12 Monthly difference toward Brewer triade mean [%] B040B072 B156

13. 13 Outline of the presentation n Examples of ozone time series measured in Switzerland : Arosa, Payerne, and Nairobi n Data quality control: Brewer triade stability n Applied research : Automated Dobson

14. 14 From a «classical» manual Dobson to …

15. 15.. an automated Dobson system Wavelength selector Attenuator

16. 16 Sun tracking mechanisms Sun elevation Sun azimuth

17. 17 Dobson: from manual to automated measurements Manual operation impacts the reproducibility, the measurement frequency and the costs. Time series for Brewer 040 and automated Dobson 062 07:0008:0009:0010:0011:0012:0013:0014:00 340 345 350 355 360 Time Total ozone column [DU] 14/04/2014

18. 18 Summary n Our main goal is to provide highest quality and longest possible time series of ozone to the scientific community n Monitoring implies  Long-term support  Scientific accompaniment of data acquisition (QA/QC)  Good collaboration between monitoring stations and scientific laboratories and Universities

19. 19 Outline of the presentation: n Examples of ozone time series measured in Switzerland : Arosa, Payerne, and Nairobi n Data quality control: Brewer triade stability n Applied research : Automated Dobson

20. 20 MATCH principle : sondes vs. MOZAIC O 3 data n PhD work of J. Staufer (ETH / MeteoSwiss) n Two independent systems are measuring ozone in air parcels along trajectories: sondes and aircrafts ( MOZAIC ) n Trajectory model LAGRANTO driven by 6-hourly ERA- interim

21. 21 Dobson pictures

22. 22 Example of Nairobi ozone sounding ECC sensing solution change => homogeneisation

23. 23 Payerne – MOZAIC: summary n (c) LS (p p trop +15 hPa)

24. 24 Example of Brewer – Dobson pairs Data B040 B156 D062D051

25. 25 MATCH applied to MLS: extend to global network ±2◦lat. ±2◦long. one day MATC H approa ch: -75 km -3 days

26. 26 Sites characteristics : Arosa vs. Davos Arosa (LKO)Davos (WRC) n Altitude1847 msl1590 msl (alt.diff. => diff. ozone column ~ 0,3% based on surface ozone) n OrientationSlope SESlope NE n Situationabove villagenear valley ground forest behind stationopen landscape no traffic aroundnear main traffic road n Horizon similar on both stations (see figure)

27. 27 Brewer at LKO/Dav: year 2010/2011 vs. 2012/2014 B040 / B072 at ArosaB040 / B072 at Davos

28. 28 Brewer at LKO: year Dec. 2010 – Nov. 2011 B040 / B072 at ArosaB040 / B072 at Davos B040 / B156 at ArosaB156 / B072 at Davos

29. 29 Difference “individuals – triade mean” [%] B040B072 B156